function checkform (form)
{
   if (form.zlecajacy.value == "") {
     alert( "Podaj Zlecajacego" );
     return false ;}
     
   if (form.telefon.value == "") {
     alert( "Podaj numer telefonu" );
     return false ;}

   if (form.email.value == "") {
     alert( "Podaj adres e-mail" );
     return false ;}
   return true ;
}